ADS-B cable length

Hi,

I want to be a volunteer for ADS-B receiver. My apartment is on the second floor and the roof is 25 meters away from me. So I need longer H155 Coax cable. First, I read the equipment instruction and it is written that cable length have to be max. 10 meters. Do you think is that a problem? Second, If it is not a problem, how can I provide the longer cable? I searched on the net but this cable is really hard to find.

It would be a shame not to use the platform of your building.
There is a simple solution. You just need to acquire a 1090 Mhz preamp.
30 dB of gain will be enough to compensate for the loss of your coaxial cable.
Alternatively, bring the internet signal and 220 volts on the roof and make the connections in a waterproof box.